gali12345

After weeks and quite a bit of back and forth, the engineer at Microchip said that he can not reproduce the problem… They seem to threat this issue as an isolated case even though I keep mentioning that other people are having this same issue (wrong PCM_CLK speed ~12MHz and non valid PCM_OUT signal). I believe that it would help if other people experiencing this problem would open a ticket at: http://www.microchip.com/support/List.aspx. It takes only a few minutes.

I have opened a ticket for this issue earlier this summer. Here is the Microchip support answer:

I have received confirmation that the firmware which ships with the RN52 does not support turning off the notification sounds.
You could try to request a custom firmware, which would support this feature. This can be done by submitting a Non Standard Customer Action Request (NSCAR) at your local Microchip Sales office: www.microchip.com/sales
This may require a business case.

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